钢骨混凝土柱正截面承载力计算的叠加方法

The Universal Superposition Method for Calculating Flexural Strength of SRC Column

根据塑性理论下限定理,对于给定的轴向力,由平衡条件任意分配钢骨部分和钢筋混凝土部分承担的轴力,并分别求得相应各部分的受弯承载力,两部分受弯承载力之和的最大值,即为钢骨混凝土柱在该轴力下的受弯承载力。本文针对工程中常用的对称配筋形式,推导出解析解,解决了直接采用一般叠加方法计算钢骨混凝土柱正截面承载力反复试算的困难,讨论了钢骨部分和钢筋混凝土部分所承担轴力比例的影响因素,并在大量计算分析的基础上,提出了简化的计算方法,为一般叠加方法的工程应用提供了理论基础和简捷的计算方法。

Based on the lower limit principle of plastic theory, the given axial force can be arbitrarily distributed to the steel and the reinforced concrete according to the equilibrium condition. The bending strength of its relative parts can be calculated respectively. The maximum value of the sum of bending strength of the steel and the reinforced concrete is the bending strength of the steel reinforced concrete (SRC). In this paper, for symmetrical reinforcement, the formulas for calculating the axial force distribution are derived. As a result, the universal superposition is no longer in need of repeatedly trial calculation. The effect of steel and reinforcement in column on the axial force distribution is investigated as well. According to the analysis of the results of a large number of calculations, the simplified method for calculating the axial force distribution has been presented. An example is provided to demonstrate the suggested method.